Avoid buprenorphine; naloxone coadministration with other CNS depressants unless no other alternatives are available, as coadministration significantly increases the risk for respiratory depression, low blood pressure, and death. If buprenorphine; naloxone must be administered to patients with pulmonary disease (i.e., asthma, chronic obstructive pulmonary disease (COPD), chronic bronchitis, cor pulmonale, emphysema, hypercapnia, hypoxia, respiratory insufficiency), use extreme caution and initiate treatment at the lowest effective dose. Clinically significant CNS and respiratory depression may occur with therapeutic doses of buprenorphine; naloxone. Patients should be warned that this medication can impair the mental and physical abilities required for activities requiring coordination and concentration including driving or operating machinery. These effects may persist for varying periods of time after dosing. Impairment of mental or physical abilities may change during dosage adjustments. Patients with suicidal ideation may not be good candidates for buprenorphine; naloxone receipt due to the possible CNS depressive effects. The risk of respiratory depression and prolonged CNS depression is increased in patients with ethanol intoxication. Buprenorphine; naloxone should also be used with caution in patients with a history of delirium tremens, heart failure, or kyphoscoliosis. Patients with kyphoscoliosis may have difficulty breathing due to their spine curvature.

DEA CLASS

Rx, schedule III

DESCRIPTION

Sublingual semisynthetic mixed opiate agonist-antagonist; opiate antagonist naloxone included as an abuse deterrentUsed for induction treatment in patients dependent on heroin or other short-acting opioids who are in opioid withdrawal; also used for maintenance treatment of opioid dependencePrescribers must comply with the requirements of the Drug Addiction Treatment Act (DATA)

DOSAGE & INDICATIONS

for induction treatment in patients dependent on heroin or other short-acting opioid products who are in opioid withdrawal.

Sublingual dosage (i.e., Suboxone sublingual film)

Adults and Adolescents 16 years of age and older

Although Suboxone sublingual (SL) film may be administered buccally during maintenance therapy, exposure to naloxone is somewhat higher after buccal use than sublingual use. Therefore, ONLY the sublingual route should be used during induction to minimize exposure to naloxone and reduce the risk of precipitating withdrawal. DAY 1 DOSING: First induction dose buprenorphine/naloxone 2 mg/0.5 mg or 4 mg/1 mg SL film; may titrate in 2 or 4 mg increments of buprenorphine, at approximately 2-hour increments, under supervision, up to a total dose of buprenorphine/naloxone 8 mg/2 mg SL film. DAY 2 DOSING: A single daily dose of buprenorphine/naloxone up to 16 mg/4 mg SL film is recommended. DAY 3 DOSING AND BEYOND: Progressively adjust dose in increments/decrements of 2 mg/0.5 mg or 4 mg/1 mg to a level that holds the patient in treatment and suppresses opioid withdrawal signs and symptoms. Consider the frequency of visits when prescribing the amount of medication; multiple refills are not advised early in treatment or without appropriate patient follow-up visits. An adequate maintenance dose should be attained as quickly as possible; in some studies, prolonged induction over several days resulted in a high drop-out rate. Use as part of a comprehensive treatment plan which includes counseling and psychosocial support. To avoid precipitating withdrawal, only initiate the first induction dose when objective signs of moderate withdrawal appear and not less than 6 hours after the patient last used an opioid. Not indicated for induction in patients dependent on methadone or long-acting opioids because these patients may be more susceptible to precipitated and prolonged withdrawal during induction than patients on short-acting agents. Prior to induction therapy, consider the type of opioid dependence (i.e., short- or long-acting opioids), the time since last opioid use, and the severity of opioid dependence. NOTE: Under the Drug Addiction Treatment Act (DATA), physicians with a current waiver to provide medication-assisted treatment (MAT) to a maximum of 100 opioid-dependent patients and who have maintained the waiver in accordance with applicable statutory requirements without interruption for at least 1 year may become eligible to provide MAT to a total of 275 opioid-dependent patients at any one time if the requirements of DATA are met.

Sublingual dosage (i.e., Zubsolv sublingual tablet)

Adults and Adolescents 16 years of age and older

The induction dosing for Zubsolv is as follows: DAY 1 DOSING: Initial recommended induction dose is 1.4 mg/0.36mg SL. During the remainder of Day 1, may administer 1 to 2 SL tablets of buprenorphine/naloxone 1.4 mg/0.36 mg SL at 1.5 to 2 hour intervals up to a total of 5.7 mg/1.4 mg. Some patients (e.g., those with recent exposure to buprenorphine) may tolerate up to 3 tablets (1.4 mg/0.36 mg per tablet) as a single, second SL dose. DAY 2 DOSING: A single daily dose of up to 11.4 mg/2.9 mg SL is recommended. Base dosage on clinical need to control acute withdrawal symptoms and administer under supervision. DAY 3 DOSING AND BEYOND: Maintenance target dose is 11.4 mg/2.9 mg SL as a single daily dose. See maintenance treatment section of product label for detailed dosing instructions. Consider the frequency of visits when prescribing the amount of medication; multiple refills are not advised early in treatment or without appropriate patient follow-up visits. Use as part of a comprehensive treatment plan which includes counseling and psychosocial support. To avoid precipitating withdrawal, only initiate the first induction dose when objective signs of moderate withdrawal appear and not less than 6 hours after the patient last used an opioid. Not indicated for induction in patients dependent on methadone or long-acting opioids because these patients may be more susceptible to precipitated and prolonged withdrawal during induction than patients on short-acting agents. Prior to induction therapy, consider the type of opioid dependence (i.e., short- or long-acting opioids), the time since last opioid use, and the severity of opioid dependence. NOTE: Under the Drug Addiction Treatment Act (DATA), physicians with a current waiver to provide medication-assisted treatment (MAT) to a maximum of 100 opioid-dependent patients and who have maintained the waiver in accordance with applicable statutory requirements without interruption for at least one year may become eligible to provide MAT to a total of 275 opioid-dependent patients at any one time if the requirements of DATA are met.

For maintenance treatment in patients with opioid dependence.

Sublingual or Buccal dosage (i.e., Suboxone sublingual film)

Adults and Adolescents 16 years of age and older

Following induction, a target maintenance dose of buprenorphine/naloxone (Suboxone) 16 mg/4 mg sublingual film once daily is suggested, given either sublingually or by the buccal route. However, doses ranging from 4 mg/day to 24 mg/day of the buprenorphine component may be required. Titrate dosage in increments of 2 mg/day to 4 mg/day of buprenorphine to a dose that holds the patient in treatment and suppresses opiate withdrawal symptoms. Higher dosages (12 mg/day to 16 mg/day of buprenorphine) have been associated with reduced opiate craving and fewer opiate-positive urine tests. Doses higher than 24 mg buccally or sublingually once daily have not shown any added benefit. NOTE: Buccal administration is not recommended during induction treatment since naloxone exposure is higher with the buccal route than the sublingual route; however, buprenorphine exposure is similar between the buccal and sublingual route. Therefore, during maintenance treatment, patients can switch between buccal and sublingual administration without significant risk of under or overdosing. Buprenorphine/naloxone should be used as part of a comprehensive treatment plan which includes counseling and psychosocial support. NOTE: Under the Drug Addiction Treatment Act (DATA), physicians with a current waiver to provide medication-assisted treatment (MAT) to a maximum of 100 opioid-dependent patients and who have maintained the waiver in accordance with applicable statutory requirements without interruption for at least 1 year may become eligible to provide MAT to a total of 275 opioid-dependent patients at any one time if the requirements of DATA are met.

Following induction, a target maintenance dose of buprenorphine/naloxone (Suboxone or generic equivalent) 16 mg/4 mg SL once daily is suggested. However, doses ranging from 4 mg/day to 24 mg/day of the buprenorphine component may be required. Titrate dose in increments of 2 mg/day to 4 mg/day of buprenorphine to a dose that holds the patient in treatment and suppresses opiate withdrawal symptoms. Higher dosages (12 mg/day to 16 mg/day of buprenorphine) have been associated with reduced opiate craving and fewer opiate-positive urine tests. Doses higher than 24 mg SL once daily have not shown any added benefit. Use as part of a comprehensive treatment plan which includes counseling and psychosocial support. REDUCING DOSAGE AND STOPPING TREATMENT: Duration of treatment and the best method for drug discontinuation have not been determined; both abrupt discontinuation and dose tapering have been used. Withdrawal symptoms may occur upon discontinuation of buprenorphine/naloxone. ALTERNATIVE MAINTENANCE DOSE REGIMEN†: Off-label regimens include 3 times per week dosing; the total weekly dose is divided and given in 3 doses over the week. NOTE: Under the Drug Addiction Treatment Act (DATA), physicians with a current waiver to provide medication-assisted treatment (MAT) to a maximum of 100 opioid-dependent patients and who have maintained the waiver in accordance with applicable statutory requirements without interruption for at least 1 year may become eligible to provide MAT to a total of 275 opioid-dependent patients at any one time if the requirements of DATA are met.

Bunavail should be used in patients who have been inducted using buprenorphine sublingual (SL) tablets. Because of the differences in bioavailability, a different dose strength is used for this product compared to the other dose forms as follows: 8 mg/2 mg Suboxone generic SL tablet provides equivalent exposure to 4.2 mg/0.7 mg Bunavail buccal film. Following induction a target maintenance dose of 8.4 mg/1.4 mg buprenorphine/naloxone buccally once daily is suggested. However, doses ranging from 2.1 mg/day to 12.6 mg/day of buprenorphine may be required. Adjust maintenance dosage in increments/decrements of 2.1 mg/day of buprenorphine to a dose that holds the patient in treatment and suppresses opiate withdrawal symptoms. Buprenophine buccal doses above 12.6 mg/day have not shown any added benefit. Use as a part of a comprehensive treatment plan which includes counseling and psychosocial support. NOTE: Under the Drug Addiction Treatment Act (DATA), physicians with a current waiver to provide medication-assisted treatment (MAT) to a maximum of 100 opioid-dependent patients and who have maintained the waiver in accordance with applicable statutory requirements without interruption for at least 1 year may become eligible to provide MAT to a total of 275 opioid-dependent patients at any one time if the requirements of DATA are met.

DOSING CONSIDERATIONS

Hepatic Impairment

Mild hepatic impairment: No dosage adjustments are necessary.

Moderate hepatic impairment: Use for maintenance therapy may not be appropriate due to increased exposure of naloxone and the possibility of precipitating opiate withdrawal. Buprenorphine; naloxone products may be used with caution and close monitoring for maintenance therapy in patients who have initiated treatment on a buprenorphine product without naloxone.

Severe hepatic impairment: Use should be avoided.

Renal Impairment

Specific guidelines for dosage adjustments in renal impairment are not available; however, dosage adjustments may be necessary. Dosage should be adjusted based on clinical response.

ADMINISTRATION

For storage information, see specific product information within the How Supplied section.

Oral Administration

Under the Drug Addiction Treatment Act (DATA), physicians with a current waiver to provide medication-assisted treatment (MAT) to a maximum of 100 opioid-dependent patients and who have maintained the waiver in accordance with applicable statutory requirements without interruption for at least 1 year may become eligible to provide MAT to a total of 275 opioid-dependent patients at any 1 time. The requirements of DATA must be met.Pharmacists who wish to verify whether a physician is qualified to prescribe buprenorphine; naloxone under the Drug Addiction Treatment Act may contact 1-866-BUP-CSAT.

Oral Solid Formulations

Sublingual tablet administration (Suboxone generic equivalent sublingual tablets):For sublingual use only.Place tablet under tongue to dissolve; allow the tablet to completely dissolve.Do not swallow or chew the tablets. Instruct patients to be consistent with tablet administration; swallowing the tablet will reduce the bioavailability of the drug.For doses requiring more than 2 tablets/dose, advise patients to either place all the tablets under the tongue at once or, if they cannot fit more than 2 tablets comfortably, place 2 tablets at a time under the tongue. With either option, patients should hold the tablets under the tongue until they completely dissolve.

Sublingual tablet administration (Zubsolv sublingual tablets):For sublingual use only.Place tablet under tongue to dissolve; allow the tablet to completely dissolve.Do not cut, chew, or swallow the tablets as this will reduce the bioavailability of the drug.For doses requiring more than 1 tablet, advise the patient to place all tablets in different places under the tongue at the same time. If a sequential mode of administration is preferred, patients should follow the same manner of dosing with continued use of the product, to ensure consistency in bioavailability.Advise patients not to eat or drink anything until the tablet is completely dissolved.

Sublingual film administration (Suboxone sublingual film):For sublingual use as directed.Do not cut, chew, or swallow the sublingual film.The foil package should not be opened until the patient is ready to use the medication. The foil package should be opened by folding along the dotted lines and tearing down at slits or cutting with scissors along the arrow. After opening, the film should be used right away.Before taking the medication, drink water to moisten the inside of the mouth. This helps the film dissolve more easily.Place film under tongue; allow the film to completely dissolve.Do not move the film once placed as this will reduce the bioavailability of the drug.For doses requiring more than 1 film/dose, advise the patient to place the films on opposite sides of the mouth under the tongue; avoid letting the films touch.Proper administration technique should be demonstrated to the patient.Dispose of unneeded medication as soon as possible by removing the buprenorphine; naloxone film from the protective foil and flushing the medication down the toilet; do not flush foil pouches or any other packaging.

Buccal administration of sublingual film (Suboxone sublingual film for buccal use):For buccal use as directed.Do not cut, chew, or swallow the film.The foil package should not be opened until the patient is ready to use the medication. The foil package should be opened by folding along the dotted lines and tearing down at slits or cutting with scissors along the arrow. After opening, the film should be used right away.Before taking the medication, drink water to moisten the inside of the mouth. This helps the film dissolve more easily.Place one film on the inside of the right or left cheek and allow to dissolve completely.If an additional film is necessary to achieve the prescribed dose, place an additional film on the inside of the opposite cheek and allow to dissolve completely.If a third film is necessary to achieve the prescribed dose, place it on the inside of the right or left cheek after the first two films have dissolved.Do not move the the film after placement since this will reduce the bioavailability of the drug.Proper administration technique should be demonstrated to the patient.Dispose of unneeded medication as soon as possible by removing the buprenorphine; naloxone film from the protective foil and flushing the medication down the toilet; do not flush foil pouches or any other packaging.

Buccal film administration (Bunavail buccal film):For buccal use only as directed.Do not open the foil package until you are ready to use the buprenorphine; naloxone buccal film. Open the foil package by folding along the dotted lines and tearing down at slits or cut with scissors in the direction of the arrows. After opening, use the film right away.Use the tongue to wet the inside of the cheek or rinse the mouth with water to moisten the area immediately before placement of the film.Hold the film with clean, dry fingers with the text (BN2, BN4, or BN6) facing up.Place the side of the film with the text (BN2, BN4, or BN6) against the inside of the moistened cheek.Press and hold the film in place for 5 seconds.The film will stick to the inside of your cheek; leave the film in place until it completely dissolves.If multiple films need to be administered, immediately apply the next film according to the steps above. Note that when two films are required for one dose, one film should be placed on the inside of one cheek and the other film on the inside of the other cheek. For doses requiring 3 films, place it on the inside of the right or left cheek after the first 2 films have dissolved.Avoid touching or moving the film(s) with the tongue or finger(s).Avoid drinking or eating food until the film(s) dissolve.Do not chew or swallow the film, as this may result in lower peak concentrations and lower bioavailability.Use the entire film; do not cut or tear it.

CONTRAINDICATIONS / PRECAUTIONS

General Information

NOTE: This monograph discusses a combination product of buprenorphine and naloxone indicated for the treatment of opioid dependence. When buprenorphine; naloxone is administered sublingually, the naloxone component produces no clinically significant effect; however, after administering parenterally, naloxone-induced opioid antagonism occurs resulting in symptoms of withdrawal.

NOTE: Buprenorphine; naloxone is a schedule C-III controlled substance. Practitioners using buprenorphine with naloxone for the treatment of opiate dependence must comply with the Drug Addiction Treatment Act of 2000 (DATA) [21 U.S.C. 823(g)]. In addition, certified physicians may only treat up to 30 patients with buprenorphine containing tablets; after holding certification for at least 1 year, physicians may submit a second notification to treat up to 100 patients.

Opiate agonist hypersensitivity

True hypersensitivity reactions are rare, caution is advised in patients with known or suspected opiate agonist hypersensitivity. Administration of buprenorphine; naloxone tablets is contraindicated in patients with buprenorphine hypersensitivity or naloxone hypersensitivity.

Despite FDA approval for treatment of opioid dependence, patients receiving buprenorphine; naloxone may still experience withdrawal effects, especially during the induction phase. Discontinuation of buprenorphine; naloxone may result in symptoms of withdrawal. The best method for buprenorphine discontinuation has not been determined; both abrupt discontinuation and tapering have been used. In addition, if buprenorphine; naloxone is misused and given via parenteral administration, withdrawal effects are highly likely due to the naloxone component. The inappropriate intravenous administration of buprenorphine in combination with benzodiazepines has resulted in fatalities (see Drug Interactions); patients should be warned about the danger of self-administering buprenorphine with any other drug with depressant properties.

Dental work, surgery

Tolerance to the analgesic effect of buprenorphine; naloxone therapy has not been documented, thus patients receiving opioid dependence therapy may be under-treated or denied pain treatment. Prior to surgery or dental work, assess and discuss pain management with patients receiving treatment for opioid dependence.

Anxiety

Buprenorphine; naloxone, as used in the treatment of opiate dependent patients, does not have antianxiety effects. Patients who are maintained on buprenorphine will react to life problems and stress with the same anxiety symptoms as other individuals. Avoid confusing such symptoms with those of opiate abstinence and do not treat anxiety by increasing the dosage of buprenorphine. The action of buprenorphine in maintenance treatment is limited to the control of opiate withdrawal symptoms and is not effective in the treatment of anxiety.

Buprenorphine; naloxone should be used cautiously in patients with GI disease including GI obstruction or ileus, acute abdomen, toxic megacolon, recent gastrointestinal tract surgery, infectious diarrhea, ulcerative colitis, or preexisting constipation due to the negative effects on peristalsis. Patients with ulcerative colitis or other inflammatory bowel disease may be more sensitive to the constipating effects of opiate agonists. Although opiate agonists are usually contraindicated for use in patients with diarrhea secondary to poisoning or infectious diarrhea, antimotility agents have been used successfully in these patients. If possible, this medicine should not be given until the toxic substance has been eliminated.

Accidental exposure, children, infants, neonates

The safe and effective use of buprenorphine; naloxone for the treatment of opioid dependence has not been established in neonates, infants, children and adolescents less than 16 years of age. Buprenorphine can cause severe, possibly fatal, respiratory depression, particularly in pediatric patients with accidental exposure to these products. Store buprenorphine-containing medications safely out of the sight and reach of children and destroy any unused medication appropriately.

Avoid buprenorphine; naloxone coadministration with other CNS depressants unless no other alternatives are available, as coadministration significantly increases the risk for respiratory depression, low blood pressure, and death. If buprenorphine; naloxone must be administered to patients with pulmonary disease (i.e., asthma, chronic obstructive pulmonary disease (COPD), chronic bronchitis, cor pulmonale, emphysema, hypercapnia, hypoxia, respiratory insufficiency), use extreme caution and initiate treatment at the lowest effective dose. Clinically significant CNS and respiratory depression may occur with therapeutic doses of buprenorphine; naloxone. Patients should be warned that this medication can impair the mental and physical abilities required for activities requiring coordination and concentration including driving or operating machinery. These effects may persist for varying periods of time after dosing. Impairment of mental or physical abilities may change during dosage adjustments. Patients with suicidal ideation may not be good candidates for buprenorphine; naloxone receipt due to the possible CNS depressive effects. The risk of respiratory depression and prolonged CNS depression is increased in patients with ethanol intoxication. Buprenorphine; naloxone should also be used with caution in patients with a history of delirium tremens, heart failure, or kyphoscoliosis. Patients with kyphoscoliosis may have difficulty breathing due to their spine curvature.

Decreased respiratory function and bradycardia can produce cerebral hypoxia and raise intracranial pressure due to carbon dioxide retention. Buprenorphine may itself elevate cerebrospinal fluid pressure and cause bradycardia and buprenorphine; naloxone should be used with caution in patients with head trauma, hypoxemia, hypercapnia, intracranial mass, intracranial hypertension, and other circumstances associated with increased intracranial pressure. Additionally, buprenorphine may cause sedation and pupillary changes such as miosis that may obscure the clinical evaluation and course of head injury or coma.

Obstetric delivery, pregnancy

Buprenorphine; naloxone is classified as FDA pregnancy category risk C; there have been no studies of buprenorphine with naloxone in pregnant women. Buprenorphine; naloxone should be used during pregnancy only if the potential benefit to the mother justifies the potential risk to the fetus. Although limited data on the use of buprenorphine during pregnancy have not shown an increased risk of major malformations, neonatal withdrawal, including symptoms of hypertonia, tremor, agitation, and myoclonus, has been reported in infants of mothers taking buprenorphine during pregnancy. There have also been rare reports of convulsions and 1 report of apnea and bradycardia. The onset of withdrawal symptoms has occurred between day 1 and day 8 of life with most occurring on day 1. Opiate dependence during pregnancy has been associated with low birth weight in the newborn, preterm birth, and fetal death. Reproductive and developmental studies in rats and rabbits have demonstrated dystocia, increased neonatal death, and developmental delays in the offspring. Acephalus, omphalocele, skeletal abnormalities, and embryofetal death have been observed; however, a clear association to drug therapy has not been established. Use of buprenorphine prior to obstetric delivery can result in respiratory depression in the newborn; therefore, an opiate antagonist, such as naloxone, should be available for respiratory depression reversal.

Breast-feeding

According to the manufacturer, caution should be exercised when buprenorphine; naloxone is administered to a breast-feeding woman, and the infant should be monitored for increased drowsiness and breathing difficulties. Limited data indicate that buprenorphine and its metabolite norbuprenorphine are present in human milk and infant urine at low levels, but no adverse reactions have been observed in the breastfed infants. In one study of 6 lactating women who were taking a median oral dose of buprenorphine of 0.29 mg/kg/day 5—8 days post-delivery, the breast milk contained buprenorphine and norbuprenorphine equal to 0.2% and 0.12%, respectively, of the maternal weight-adjusted dose. In a separate study of 7 lactating women, the median oral dose of buprenorphine was 7 mg/day an average of 1.12 months post-delivery. Assuming a milk consumption of 150 ml/kg/day, an exclusively breastfed infant would have received a dose of buprenorphine and norbuprenorphine that were 0.38% and 0.18%, respectively, of the maternal weight-adjusted dose. The American Academy of Pediatrics (AAP) has not assessed the safety of either ingredient of buprenorphine; naloxone during breast-feeding; however, the AAP has considered methadone to be a medication that is usually compatible with breast-feeding. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally ingested drug, healthcare providers are encouraged to report the adverse effect to the FDA.

Hepatic disease, hepatic encephalopathy, hepatitis, jaundice

Buprenorphine; naloxone products should be avoided in patients with severe hepatic disease and may not be appropriate in patients with moderate hepatic impairment. Hepatic impairment causes a reduction in naloxone clearance that is much greater than the effect on buprenorphine clearance, and patients with moderate to severe hepatic impairment will be exposed to significantly higher levels of naloxone than patients with normal hepatic function. This may result in an increased risk of precipitated withdrawal during induction treatment and a reduction in the efficacy of buprenorphine throughout treatment. Buprenorphine; naloxone may be used with caution and close monitoring for maintenance therapy in patients with moderate hepatic impairment who have initiated treatment on a buprenorphine product without naloxone. Cytolytic hepatitis, hepatitis with jaundice, hepatic failure, hepatic necrosis, hepatorenal syndrome, and hepatic encephalopathy have been reported during clinical trial evaluation and post-marketing use of buprenorphine; naloxone. In many cases, pre-existing elevations in LFTs, hepatitis B or C infections, concurrent use of hepatotoxic drugs, or ongoing injecting drug use may have contributed to or caused further hepatic injury during treatment with buprenorphine; naloxone. Baseline assessment of LFTs and periodic evaluation throughout treatment are recommended.

Patients with renal impairment or renal failure may have an exaggerated response to buprenorphine; naloxone, since about 30% of a dose is excreted in the urine as buprenorphine, norbuprenorphine, and their metabolites. However, only 1% of buprenorphine and 2.7% of norbuprenorphine are excreted in the urine as free forms. Buprenorphine can also cause urinary retention and oliguria, due to increasing the tension of the detrusor muscle. Patients more prone to urinary retention include those with bladder obstruction, prostatic hypertrophy, urinary tract obstruction, urethral stricture, recent urinary tract surgery, or renal disease.

Buprenorphine has been shown to increase intracholedochal pressure to a similar degree as other opiate agonists and thus, buprenorphine; naloxone should be administered with caution to patients with biliary tract disease such as those with gallbladder disease, gallstones, biliary obstruction, or biliary cirrhosis.

Opioid-naive patients

Buprenorphine; naloxone is not appropriate for use as an analgesic. There have been deaths reported in opioid-naive patients who received a 2 mg dose of buprenorphine as a sublingual tablet for analgesia.

Geriatric

Caution is advised for use of buprenorphine; naloxone in geriatric patients, since they may be more sensitive to the respiratory and CNS depressant effects of the drug. Clinical studies of buprenorphine; naloxone products have not included sufficient numbers of subjects aged 65 years and over to determine whether they respond differently than younger adults in opioid dependency treatment. In general, dose selection for a geriatric patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, respiratory, or cardiac function, and of concomitant disease or other drug therapy.

Adrenal insufficiency, hypothyroidism, myxedema

Use buprenorphine with caution in patients with adrenal insufficiency (i.e., Addison's disease), hypothyroidism, or myxedema. Such patients may be at increased risk of adverse events. Opioids inhibit the secretion of adrenocorticotropic hormone (ACTH), cortisol, and luteinizing hormone (LH); however, the thyroid stimulating hormone may be either stimulated or inhibited by opioids. Rarely, adrenal insufficiency has been reported in association with opioid use. Patients should seek immediate medical attention if they experience symptoms such as nausea, vomiting, loss of appetite, fatigue, weakness, dizziness, or hypotension. If adrenocortical insufficiency is suspected, confirm with diagnostic testing as soon as possible. If diagnosed, the patient should be treated with physiologic replacement doses of corticosteroids, and if appropriate, weaned off of opioid therapy. If the opioid can be discontinued, a follow-up assessment of adrenal function should be performed to determine if corticosteroid treatment can be discontinued. Other opioids may be tried; some cases reported use of a different opioid with no recurrence of adrenocortical insufficiency. It is unclear which, if any, opioids are more likely to cause adrenocortical insufficiency. In addition, chronic opioid use may lead to symptoms of hypogonadism, resulting from changes in the hypothalamic-pituitary-gonadal axis. Monitor patients for symptoms of opioid-induced endocrinopathy, particularly those receiving a daily dose equivalent to 100 mg or more of morphine. Patients presenting with signs or symptoms of androgen deficiency should undergo laboratory evaluation.

DRUG INTERACTIONS

Acetaminophen; Butalbital; Caffeine; Codeine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as codeine. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of codeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including codeine. Acetaminophen; Caffeine; Dihydrocodeine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as dihydrocodeine. Dihydrocodeine is found in several combination cough products. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression if buprenorphine is used with dihydrocodeine. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of dihydrocodeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including dihydrocodeine. Acetaminophen; Caffeine; Magnesium Salicylate; Phenyltoloxamine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Acetaminophen; Caffeine; Phenyltoloxamine; Salicylamide: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Acetaminophen; Chlorpheniramine; Phenylephrine; Phenyltoloxamine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Acetaminophen; Codeine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as codeine. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of codeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including codeine. Acetaminophen; Dextromethorphan; Doxylamine: If concurrent use of doxylamine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Acetaminophen; Diphenhydramine: If concurrent use of diphenhydramine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Increased sedation, coma, and respiratory depression may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Acetaminophen; Hydrocodone: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as hydrocodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. The opiate antagonists naloxone and naltrexone are pharmacologic opposites of hydrocodone. These drugs can block the actions of hydrocodone and, if administered to patients who have received chronic hydrocodone, can produce acute withdrawal and/or reduce the analgesic effect of hydrocodone. Acetaminophen; Oxycodone: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as oxycodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of oxycodone in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including oxycodone. Acetaminophen; Pentazocine: Concomitant use of buprenorphine with other CNS depressants can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Naloxone reverses the analgesic and adverse effects of opiate agonists and mixed opiate agonists/antagonists (e.g., buprenorphine, butorphanol, nalbuphine, and pentazocine). Reversal of respiratory depression by partial agonists or mixed agonist/antagonists may be incomplete or require higher doses of naloxone. For example, large doses of naloxone are required to antagonize buprenorphine. Buprenorphine antagonism is characterized by a gradual onset of the reversal effects and a decreased duration of action of the normally prolonged respiratory depression. Respirations should be mechanically assisted as clinically indicated. Patients with severe pain or patients who are physically dependent on opiate analgesics can experience severe pain or withdrawal symptoms, respectively. Methohexital appears to block the acute onset of withdrawal symptoms induced by naloxone in opiate addicts. Clinicians should be prepared to manage possible reactions after naloxone administration. Acetaminophen; Propoxyphene: Buprenorphine may partially block the analgesic, respiratory depressant and CNS depressant effects of pure opiate agonists due to the fact that buprenorphine is a partial mu-receptor agonist that has greater receptor affinity than many full agonists. Buprenorphine may also be used concurrently with some opioid agonists, and additive CNS depressive effects are possible. Hypotension, profound sedation, coma, respiratory depression, or death may occur. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Any effect of buprenorphine may last for several days, since buprenorphine dissociates from the mu-receptor very slowly. Due to the mu-receptor high affinity binding, buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists. The additive or antagonistic effects are dependent upon the dose of pure opiate agonist used; antagonistic effects are more common at low to moderate doses of the pure opioid agonist. Propoxyphene is a centrally acting narcotic analgesic agent. Naloxone is a pharmacologic opposite of propoxyphene. Naloxone can block the actions of propoxyphene. Tolerance and physical dependence can occur in patients who take excessive propoxyphene doses over time and thus, acute withdrawal and/or pain recurrence may occur if naloxone is administered. Acetaminophen; Tramadol: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as tramadol. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Additionally, concurrent use of opiates with other drugs that modulate serotonergic function, such as tramadol, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. There is also a potential for increased risk of seizures if tramadol is given with other opiates. Naloxone should be used cautiously in situations of tramadol overdose. Naloxone administration may increase the risk of seizures in these patients. Furthermore, naloxone will reverse some but not all symptoms caused by tramadol overdosage. It is not clear if such precautions would also apply to the use of other opiate antagonists with tramadol. Acrivastine; Pseudoephedrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Albuterol: Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Beta-agonists may be associated with adverse cardiovascular effects including QT interval prolongation, usually at higher doses and/or when associated with hypokalemia. This risk may be more clinically significant with long-acting beta-agonists (i.e., formoterol, arformoterol, indacaterol, olodaterol, salmeterol, fluticasone; vilanterol, umeclidinium; vilanterol) than with short-acting beta-agonists. Beta-agonists should be administered with caution to patients being treated with drugs known to prolong the QT interval because the action of beta-agonists on the cardiovascular system may be potentiated. Albuterol; Ipratropium: Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Beta-agonists may be associated with adverse cardiovascular effects including QT interval prolongation, usually at higher doses and/or when associated with hypokalemia. This risk may be more clinically significant with long-acting beta-agonists (i.e., formoterol, arformoterol, indacaterol, olodaterol, salmeterol, fluticasone; vilanterol, umeclidinium; vilanterol) than with short-acting beta-agonists. Beta-agonists should be administered with caution to patients being treated with drugs known to prolong the QT interval because the action of beta-agonists on the cardiovascular system may be potentiated. Alfentanil: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as alfentanil. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone is the pharmacologic opposite of alfentanil. Naloxone can block the analgesic, respiratory depressant and CNS depressant actions of alfentanil. During surgery naloxone should be carefully titrated to reverse undesired effects without affecting postoperative pain management. Naloxone also reverses the skeletal muscle rigidity induced by alfentanil. If naloxone is used to reverse respiratory depression caused by alfentanil, additional naloxone doses may be required. The duration of respiratory depression may last longer than the effect of naloxone. Administration of an opiate antagonist should not preclude immediate establishment of a patent airway, administration of oxygen, or implementation of assisted or controlled ventilation for hypoventilation or apnea. Alfuzosin: Buprenorphine should be used cautiously and with close monitoring with should be used cautiously and with alfuzosin. Based on electrophysiology studies performed by the manufacturer, alfuzosin has a slight effect to prolong the QT interval. The QT prolongation appeared less with alfuzosin 10 mg than with 40 mg. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Almotriptan: Concurrent use of opioids with other drugs that modulate serotonergic function, such as selective serotonin-receptor agonists ('triptans'), has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment with buprenorphine and a triptan is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Alosetron: Concurrent use of buprenorphine and antidiarrheals can lead to severe constipation and possibly additive CNS depression. Alprazolam: Concomitant use of mixed opiate agonists/antagonists with benzodiazepines may cause respiratory depression, hypotension, profound sedation, and death. Limit the use of mixed opiate agonists/antagonists with benzodiazepines to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. If a mixed opiate agonist/antagonist is initiated in a patient taking a benzodiazepine, use a lower initial dose of the mixed opiate agonist/antagonist and titrate to clinical response. Reduce injectable buprenorphine dose by 1/2, and for the buprenorphine transdermal patch, start therapy with the 5 mcg/hour patch. If a benzodiazepine is prescribed for an indication other than epilepsy in a patient taking a mixed opiate agonist/antagonist, use a lower initial dose of the benzodiazepine and titrate to clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. Alvimopan: Alvimopan is an opiate antagonist. In general, coadministration with another opiate antagonist should be avoided due to the potential for additive effect of opioid receptor antagonism and increased risk of opioid withdrawal with concomitant use. Amiodarone: Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Antiarrhythmics with an established risk for QT prolongation and TdP include disopyramide, flecainide, propafenone, quinidine (including dextromethorphan; quinidine), procainamide, amiodarone, ibutilide, and sotalol. In addition, since the metabolism of buprenorphine is mediated by CYP3A4, co-administration of a CYP3A4 inhibitor such as amiodarone may decrease the clearance of buprenorphine resulting in prolonged or increased opioid effects. If co-administration is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider dose adjustments until stable drug effects are achieved. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied. Amitriptyline: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of tricyclic antidepressants (TCAs) and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Tricyclic antidepressants share pharmacologic properties similar to the Class IA antiarrhythmic agents and may prolong the QT interval, particularly in overdose or with higher-dose prescription therapy (elevated serum concentrations). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, concurrent use of opioids with other drugs that modulate serotonergic function, such as TCAs, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Lastly, concomitant use of buprenorphine with other CNS depressants, such as TCAs, can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. Consider a dose reduction of one or both drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Amitriptyline; Chlordiazepoxide: Concomitant use of mixed opiate agonists/antagonists with benzodiazepines may cause respiratory depression, hypotension, profound sedation, and death. Limit the use of mixed opiate agonists/antagonists with benzodiazepines to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. If a mixed opiate agonist/antagonist is initiated in a patient taking a benzodiazepine, use a lower initial dose of the mixed opiate agonist/antagonist and titrate to clinical response. Reduce injectable buprenorphine dose by 1/2, and for the buprenorphine transdermal patch, start therapy with the 5 mcg/hour patch. If a benzodiazepine is prescribed for an indication other than epilepsy in a patient taking a mixed opiate agonist/antagonist, use a lower initial dose of the benzodiazepine and titrate to clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of tricyclic antidepressants (TCAs) and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Tricyclic antidepressants share pharmacologic properties similar to the Class IA antiarrhythmic agents and may prolong the QT interval, particularly in overdose or with higher-dose prescription therapy (elevated serum concentrations). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, concurrent use of opioids with other drugs that modulate serotonergic function, such as TCAs, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Lastly, concomitant use of buprenorphine with other CNS depressants, such as TCAs, can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. Consider a dose reduction of one or both drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Amoxapine: If concurrent use of amoxapine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. In addition, concurrent use of opioids with other drugs that modulate serotonergic function, such as amoxapine, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Amoxicillin; Clarithromycin; Lansoprazole: Due to the potential for QT prolongation, cautious use and close monitoring are advisable if concurrent use of clarithromycin and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Clarithromycin also has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, since the metabolism of buprenorphine is mediated by CYP3A4, co-administration of a strong CYP3A4 inhibitor such as clarithromycin may decrease the clearance of buprenorphine resulting in prolonged or increased opioid effects. If co-administration is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider dose adjustments until stable drug effects are achieved. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied, and the effect may be dependent on the route of administration. Amoxicillin; Clarithromycin; Omeprazole: Due to the potential for QT prolongation, cautious use and close monitoring are advisable if concurrent use of clarithromycin and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Clarithromycin also has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, since the metabolism of buprenorphine is mediated by CYP3A4, co-administration of a strong CYP3A4 inhibitor such as clarithromycin may decrease the clearance of buprenorphine resulting in prolonged or increased opioid effects. If co-administration is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider dose adjustments until stable drug effects are achieved. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied, and the effect may be dependent on the route of administration. Amprenavir: Since the metabolism of buprenorphine is mediated by CYP3A4, co-administration of strong CYP3A4 inhibitors such as anti-retroviral protease inhibitors (e.g., amprenavir, fosamprenavir, indinavir, nelfinavir) may result in increased systemic exposure to buprenorphine, with the potential for excessive buprenorphine-related side effects; however, studies have shown that nelfinavir has little effect on buprenorphine pharmacokinetics and no significant pharmacodynamic effects. In general, if a protease inhibitor and buprenorphine are used concurrently, monitor accordingly for sedation and respiratory depression and adjust the buprenorphine dosage if needed. Consider conservative buprenorphine therapy in patients already on a CYP3A4 inhibitor. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied. Anagrelide: Buprenorphine should be used cautiously and with close monitoring with anagrelide. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval, such as anagrelide. Torsades de pointes (TdP) and ventricular tachycardia have been reported with anagrelide. In addition, dose-related increases in mean QTc and heart rate were observed in healthy subjects. A cardiovascular examination, including an ECG, should be obtained in all patients prior to initiating anagrelide therapy. Monitor patients during coadministration of buprenorphine and anagrelide for cardiovascular effects and evaluate as necessary. Anticholinergics: Buprenorphine is an opioid analgesic. Opioids increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect. Opiate analgesics combined with antimuscarinics can cause severe constipation or paralytic ileus, especially with chronic use. In addition, concurrent use may also lead to additive CNS depression. Apomorphine: Buprenorphine should be used cautiously and with close monitoring with apomorphine. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval, such as apomorphine. Limited data indicate that QT prolongation is possible with apomorphine administration; the change in QTc interval is not significant in most patients receiving dosages within the manufacturer's guidelines. If these drugs are used together, consider the potential for additive effects on the QT interval. Aprepitant, Fosaprepitant: Use caution if buprenorphine and aprepitant, fosaprepitant are used concurrently and monitor for an increase in buprenorphine-related adverse effects for several days after administration of a multi-day aprepitant regimen. Buprenorphine is a CYP3A4 substrate. Aprepitant, when administered as a 3-day oral regimen (125 mg/80 mg/80 mg), is a moderate CYP3A4 inhibitor and inducer and may increase plasma concentrations of buprenorphine. For example, a 5-day oral aprepitant regimen increased the AUC of another CYP3A4 substrate, midazolam (single dose), by 2.3-fold on day 1 and by 3.3-fold on day 5. After a 3-day oral aprepitant regimen, the AUC of midazolam (given on days 1, 4, 8, and 15) increased by 25% on day 4, and then decreased by 19% and 4% on days 8 and 15, respectively. As a single 125 mg or 40 mg oral dose, the inhibitory effect of aprepitant on CYP3A4 is weak, with the AUC of midazolam increased by 1.5-fold and 1.2-fold, respectively. After administration, fosaprepitant is rapidly converted to aprepitant and shares many of the same drug interactions. However, as a single 150 mg intravenous dose, fosaprepitant only weakly inhibits CYP3A4 for a duration of 2 days; there is no evidence of CYP3A4 induction. Fosaprepitant 150 mg IV as a single dose increased the AUC of midazolam (given on days 1 and 4) by approximately 1.8-fold on day 1; there was no effect on day 4. Less than a 2-fold increase in the midazolam AUC is not considered clinically important. Arformoterol: Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Beta-agonists may be associated with adverse cardiovascular effects including QT interval prolongation, usually at higher doses and/or when associated with hypokalemia. This risk may be more clinically significant with long-acting beta-agonists (i.e.arformoterol) than with short-acting beta-agonists. Beta-agonists should be administered with caution to patients being treated with drugs known to prolong the QT interval because the action of beta-agonists on the cardiovascular system may be potentiated. Aripiprazole: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of aripiprazole and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). QT prolongation has occurred during therapeutic use of aripiprazole and following overdose. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If concurrent use of aripiprazole and buprenorphine is necessary, consider a dose reduction of one or both drugs. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Arsenic Trioxide: Avoid concomitant use of arsenic trioxide with other drugs that may cause QT interval prolongation, such as buprenorphine. Torsade de pointes (TdP), QT interval prolongation, and complete atrioventricular block have been reported with arsenic trioxide use. Discontinue or select an alternative drug that does not prolong the QT interval prior to starting arsenic trioxide therapy. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If concomitant drug use is unavoidable, frequently monitor electrocardiograms. Artemether; Lumefantrine: The administration of artemether; lumefantrine is associated with prolongation of the QT interval. Although there are no studies examining the effects of artemether; lumefantrine in patients receiving other QT prolonging drugs, coadministration of such drugs may result in additive QT prolongation and should be avoided. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If coadministration is necessary, consider ECG monitoring. Asenapine: Buprenorphine should be avoided in combination with asenapine. Asenapine has been associated with QT prolongation. Buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). The manufacturer of asenapine recommends avoiding coadministration with with other agents also known to prolong the QT interval. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If these drugs are used together, consider the potential for additive effects on the QT interval. Aspirin, ASA; Butalbital; Caffeine; Codeine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as codeine. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of codeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including codeine. Aspirin, ASA; Caffeine; Dihydrocodeine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as dihydrocodeine. Dihydrocodeine is found in several combination cough products. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression if buprenorphine is used with dihydrocodeine. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of dihydrocodeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including dihydrocodeine. Aspirin, ASA; Carisoprodol: Concomitant use of buprenorphine with other CNS depressants can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur; examples of other CNS depressants can include skeletal muscle relaxants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Aspirin, ASA; Carisoprodol; Codeine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as codeine. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of codeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including codeine. Concomitant use of buprenorphine with other CNS depressants can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur; examples of other CNS depressants can include skeletal muscle relaxants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Aspirin, ASA; Oxycodone: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as oxycodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of oxycodone in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including oxycodone. Atazanavir: Atazanavir-induced inhibition of CYP3A4 may increase the AUCs of buprenorphine by 93% and norbuprenorphine 76%. When buprenorphine is coadministered with atazanavir/ritonavir the AUCs of buprenophine and norbuprenorphine are increased by 66% and 105%, respectively. Serious drug interactions have been reported following administration of sublingual buprenorphine with atazanavir and atazanavir/ritonavir; although not clinically studied, atazanavir-induced inhibition of UGT1A1 may increase the potential for interaction with orally administered buprenorphine. If atazanavir plus ritonavir must be coadministered with buprenorphine, monitor patient response, including sedation and cognitive effects, and adjust the dose of buprenorphine if necessary. Buprenorphine administered with atazanavir plus ritonavir is not expected to decrease atazanavir concentrations; however, if buprenorphine is administered with atazanavir in the absence of ritonavir, atazanavir concentrations may be decreased. Do not administer atazanavir with buprenorphine with unboosted atazanavir. Atazanavir; Cobicistat: Atazanavir-induced inhibition of CYP3A4 may increase the AUCs of buprenorphine by 93% and norbuprenorphine 76%. When buprenorphine is coadministered with atazanavir/ritonavir the AUCs of buprenophine and norbuprenorphine are increased by 66% and 105%, respectively. Serious drug interactions have been reported following administration of sublingual buprenorphine with atazanavir and atazanavir/ritonavir; although not clinically studied, atazanavir-induced inhibition of UGT1A1 may increase the potential for interaction with orally administered buprenorphine. If atazanavir plus ritonavir must be coadministered with buprenorphine, monitor patient response, including sedation and cognitive effects, and adjust the dose of buprenorphine if necessary. Buprenorphine administered with atazanavir plus ritonavir is not expected to decrease atazanavir concentrations; however, if buprenorphine is administered with atazanavir in the absence of ritonavir, atazanavir concentrations may be decreased. Do not administer atazanavir with buprenorphine with unboosted atazanavir. The plasma concentrations of buprenorphine and its metabolite, norbuprenorphine, are elevated when administered concurrently cobicistat. Dose adjustents are not required; however clinical monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while buprenorphine is a CYP3A4 substrate. The plasma concentrations of buprenorphine and naloxone may be elevated when administered concurrently with cobicistat. When initiating buprenorphine; naloxone in patients currently on a regimen containing cobicistat and atazanavir or darunavir, use the lowest buprenorphine; naloxone starting dose and slowly titrate to desired effect. When initiating antiretroviral regimens containing cobicistat and atazanavir or darunavir to patients on buprenorphine; naloxone, an adjustment of buprenorphine; naloxone dose may be needed. Monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while buprenorphine is a CYP3A4 substrate. Atomoxetine: Buprenorphine should be used cautiously and with close monitoring with atomoxetine. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval, such as atomoxetine. QT prolongation has occurred during therapeutic use of atomoxetine and following overdose. If these drugs are used together, consider the potential for additive effects on the QT interval. Atropine; Benzoic Acid; Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate: Concurrent use of opioids, such as buprenorphine, with other drugs that modulate serotonergic function, such as methylene blue, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Atropine; Difenoxin: Naloxone can antagonize the therapeutic efficacy of diphenoxylate in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including diphenoxylate. Buprenorphine is an opioid analgesic. Opioids increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect. Concurrent use of buprenorphine and antidiarrheals, such as atropine; diphenoxylate, can lead to severe constipation and possibly additive CNS depression. Atropine; Diphenoxylate: Naloxone can antagonize the therapeutic efficacy of diphenoxylate in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including diphenoxylate. Buprenorphine is an opioid analgesic. Opioids increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect. Concurrent use of buprenorphine and antidiarrheals, such as atropine; diphenoxylate, can lead to severe constipation and possibly additive CNS depression. Azithromycin: Due to the potential for QT prolongation, cautious use and close monitoring are advisable if concurrent use of azithromycin and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). There have been case reports of QT prolongation and torsade de pointes (TdP) with the use of azithromycin in post-marketing reports. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, since the metabolism of buprenorphine is mediated by CYP3A4, co-administration of a CYP3A4 inhibitor such as azithromycin may decrease the clearance of buprenorphine resulting in prolonged or increased opioid effects. If co-administration is necessary, monitor patients for QT prolongation, respiratory depression and sedation at frequent intervals and consider dose adjustments until stable drug effects are achieved. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied. Baclofen: Concomitant use of buprenorphine with other CNS depressants can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur; examples of other CNS depressants can include skeletal muscle relaxants, like baclofen. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Barbiturates: Close monitoring of the patient is recommended if a CYP3A4 inducer is used with buprenorphine. Inducers of CYP3A4 such as phenobarbital may induce the hepatic metabolism of buprenorphine, which may lead to opiate withdrawal or inadequate pain control. It is likely that all barbiturates exert the same effect as phenobarbital. This interaction is most significant if the enzyme-inducing agent is added after buprenorphine therapy has begun. Buprenorphine doses may need to be increased if any of these agents are added. Conversely, buprenorphine doses may need to be decreased if these drugs are discontinued. Additive CNS depression may be the more important issue initially when barbiturates are given with buprenorphine; the induction of buprenorphine metabolism may take several days. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Bedaquiline: Buprenorphine should be used cautiously and with close monitoring with bedaquiline. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Bedaquiline has also been reported to prolong the QT interval. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Coadministration may result in additive or synergistic prolongation of the QT interval. Monitor the ECG. Belladonna; Opium: Naloxone can antagonize the therapeutic efficacy of opium in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including opium. Buprenorphine may partially block the analgesic, respiratory depressant and CNS depressant effects of pure opiate agonists due to the fact that buprenorphine is a partial mu receptor agonist that has greater receptor affinity than many full agonists. Additive CNS, respiratory, and hypotensive effects are possible with this combination. Benzoic Acid; Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate: Concurrent use of opioids, such as buprenorphine, with other drugs that modulate serotonergic function, such as methylene blue, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Bismuth Subcitrate Potassium; Metronidazole; Tetracycline: Buprenorphine should be used cautiously and with close monitoring with metronidazole. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval, such as metronidazole. Potential QT prolongation has been reported in limited case reports with metronidazole. If these drugs are used together, consider the potential for additive effects on the QT interval. Bismuth Subsalicylate; Metronidazole; Tetracycline: Buprenorphine should be used cautiously and with close monitoring with metronidazole. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval, such as metronidazole. Potential QT prolongation has been reported in limited case reports with metronidazole. If these drugs are used together, consider the potential for additive effects on the QT interval. Boceprevir: The plasma concentrations of CYP3A4 substrates such as buprenorphine and its metabolite, norbuprenorphine, may be elevated when administered concurrently with strong CYP3A4 inhibitors such as boceprevir. During co-administration, use the lowest buprenorphine starting dose and slowly titrate to desired effect. Monitoring for adverse effects, such as CNS side effects or respiratory depression, is advisable. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied. Bosentan: Bosentan is an inducer of cytochrome P450 enzymes, specifically the CYP2C9 and CYP3A4 isoenzymes, and may decrease concentrations of drugs metabolized by these enzymes, including buprenorphine. Brexpiprazole: Due to the CNS effects of brexpiprazole, caution is advisable when brexpiprazole is given in combination with other centrally-acting medications including buprenorphine or buprenorphine; naloxone. Brompheniramine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Brompheniramine; Carbetapentane; Phenylephrine: Drowsiness has been reported during administration of carbetapentane. An enhanced CNS depressant effect may occur when carbetapentane is combined with other CNS depressants. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Brompheniramine; Dextromethorphan; Guaifenesin: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Brompheniramine; Guaifenesin; Hydrocodone: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as hydrocodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. The opiate antagonists naloxone and naltrexone are pharmacologic opposites of hydrocodone. These drugs can block the actions of hydrocodone and, if administered to patients who have received chronic hydrocodone, can produce acute withdrawal and/or reduce the analgesic effect of hydrocodone. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Brompheniramine; Hydrocodone; Pseudoephedrine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as hydrocodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. The opiate antagonists naloxone and naltrexone are pharmacologic opposites of hydrocodone. These drugs can block the actions of hydrocodone and, if administered to patients who have received chronic hydrocodone, can produce acute withdrawal and/or reduce the analgesic effect of hydrocodone. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Brompheniramine; Pseudoephedrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Budesonide; Formoterol: Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Beta-agonists may be associated with adverse cardiovascular effects including QT interval prolongation, usually at higher doses and/or when associated with hypokalemia. This risk may be more clinically significant with long-acting beta-agonists (i.e., formoterol) than with short-acting beta-agonists. Beta-agonists should be administered with caution to patients being treated with drugs known to prolong the QT interval because the action of beta-agonists on the cardiovascular system may be potentiated. Buprenorphine: Naloxone reverses the analgesic and adverse effects of opiate agonists and mixed opiate agonists/antagonists (e.g., buprenorphine, butorphanol, nalbuphine, and pentazocine). Reversal of respiratory depression by partial agonists or mixed agonist/antagonists may be incomplete or require higher doses of naloxone. For example, large doses of naloxone are required to antagonize buprenorphine. Buprenorphine antagonism is characterized by a gradual onset of the reversal effects and a decreased duration of action of the normally prolonged respiratory depression. Respirations should be mechanically assisted as clinically indicated. Patients with severe pain or patients who are physically dependent on opiate analgesics can experience severe pain or withdrawal symptoms, respectively. Methohexital appears to block the acute onset of withdrawal symptoms induced by naloxone in opiate addicts. Clinicians should be prepared to manage possible reactions after naloxone administration. Bupropion; Naltrexone: When naltrexone is used as adjuvant treatment of opiate or alcohol dependence, use is contraindicated in patients currently receiving mixed opiate agonists/antagonists. Naltrexone will antagonize the therapeutic benefits of mixed opiate agonists/antagonists and will induce a withdrawal reaction in patients with physical dependence to opioids. Also, patients should be opiate-free for at least 7 to 10 days prior to initiating naltrexone therapy. If there is any question of opioid use in the past 7-10 days and the patient is not experiencing opioid withdrawal symptoms and/or the urine is negative for opioids, a naloxone challenge test needs to be performed. If a patient receives naltrexone and an opiate agonist is needed for an emergency situation, large doses of opiate agonists may ultimately overwhelm naltrexone antagonism of opiate receptors. Immediately following administration of exogenous opiate agonists, the opiate plasma concentration may be sufficient to overcome naltrexone competitive blockade, but the patient may experience deeper and more prolonged respiratory depression and thus, may be in danger of respiratory arrest and circulatory collapse. Non-receptor mediated actions like facial swelling, itching, generalized erythema, or bronchoconstriction may occur presumably due to histamine release. A rapidly acting opiate agonist is preferred as the duration of respiratory depression will be shorter. Patients receiving naltrexone may also experience opiate side effects (respiratory insufficiency or arrest or circulatory collapse) with low doses of opiate agonists. If the opiate agonist is taken in such a way that high concentrations remain in the body beyond the time naltrexone exerts its therapeutic effects, serious side effects may occur. Buspirone: If concurrent use of buspirone and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Sedation, coma, or respiratory depression may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Butorphanol: Concomitant use of buprenorphine with other CNS depressants can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Naloxone reverses the analgesic and adverse effects of opiate agonists and mixed opiate agonists/antagonists (e.g., buprenorphine, butorphanol, nalbuphine, and pentazocine). Reversal of respiratory depression by partial agonists or mixed agonist/antagonists may be incomplete or require higher doses of naloxone. For example, large doses of naloxone are required to antagonize buprenorphine. Buprenorphine antagonism is characterized by a gradual onset of the reversal effects and a decreased duration of action of the normally prolonged respiratory depression. Respirations should be mechanically assisted as clinically indicated. Patients with severe pain or patients who are physically dependent on opiate analgesics can experience severe pain or withdrawal symptoms, respectively. Methohexital appears to block the acute onset of withdrawal symptoms induced by naloxone in opiate addicts. Clinicians should be prepared to manage possible reactions after naloxone administration. Capsaicin; Metaxalone: Concomitant use of buprenorphine with other CNS depressants can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur; examples of other CNS depressants can include skeletal muscle relaxants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbamazepine: Inducers of CYP3A4 such as carbamazepine, may induce the hepatic metabolism of buprenorphine or opiate agonists, which may lead to opiate withdrawal or inadequate pain control. Carbetapentane; Chlorpheniramine: Drowsiness has been reported during administration of carbetapentane. An enhanced CNS depressant effect may occur when carbetapentane is combined with other CNS depressants. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbetapentane; Chlorpheniramine; Phenylephrine: Drowsiness has been reported during administration of carbetapentane. An enhanced CNS depressant effect may occur when carbetapentane is combined with other CNS depressants. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbetapentane; Diphenhydramine; Phenylephrine: Drowsiness has been reported during administration of carbetapentane. An enhanced CNS depressant effect may occur when carbetapentane is combined with other CNS depressants. If concurrent use of diphenhydramine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Increased sedation, coma, and respiratory depression may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbetapentane; Guaifenesin: Drowsiness has been reported during administration of carbetapentane. An enhanced CNS depressant effect may occur when carbetapentane is combined with other CNS depressants. Carbetapentane; Guaifenesin; Phenylephrine: Drowsiness has been reported during administration of carbetapentane. An enhanced CNS depressant effect may occur when carbetapentane is combined with other CNS depressants. Carbetapentane; Phenylephrine: Drowsiness has been reported during administration of carbetapentane. An enhanced CNS depressant effect may occur when carbetapentane is combined with other CNS depressants. Carbetapentane; Phenylephrine; Pyrilamine: Drowsiness has been reported during administration of carbetapentane. An enhanced CNS depressant effect may occur when carbetapentane is combined with other CNS depressants. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbetapentane; Pseudoephedrine: Drowsiness has been reported during administration of carbetapentane. An enhanced CNS depressant effect may occur when carbetapentane is combined with other CNS depressants. Carbetapentane; Pyrilamine: Drowsiness has been reported during administration of carbetapentane. An enhanced CNS depressant effect may occur when carbetapentane is combined with other CNS depressants. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbidopa; Levodopa; Entacapone: Concomitant use of opiate agonists-antagonists with other central nervous system (CNS) depressants, such as COMT inhibitors, can potentiate the effects of the opiate agonists-antagonist and may lead to additive CNS or respiratory depression. Prior to concurrent use of a mixed opiate agonist-antagonist in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. If these agents are used together, reduced dosages may be necessary. Carefully monitor the patient for hypotension, CNS depression, and respiratory depression. Carbinoxamine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbinoxamine; Dextromethorphan; Pseudoephedrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbinoxamine; Hydrocodone; Phenylephrine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as hydrocodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. The opiate antagonists naloxone and naltrexone are pharmacologic opposites of hydrocodone. These drugs can block the actions of hydrocodone and, if administered to patients who have received chronic hydrocodone, can produce acute withdrawal and/or reduce the analgesic effect of hydrocodone. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbinoxamine; Hydrocodone; Pseudoephedrine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as hydrocodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. The opiate antagonists naloxone and naltrexone are pharmacologic opposites of hydrocodone. These drugs can block the actions of hydrocodone and, if administered to patients who have received chronic hydrocodone, can produce acute withdrawal and/or reduce the analgesic effect of hydrocodone. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbinoxamine; Phenylephrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Carbinoxamine; Pseudoephedrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Cariprazine: Due to the CNS effects of cariprazine, caution is advisable when cariprazine is given in combination with other centrally-acting medications including buprenorphine or buprenorphine; naloxone. Carisoprodol: Concomitant use of buprenorphine with other CNS depressants can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur; examples of other CNS depressants can include skeletal muscle relaxants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Ceritinib: If possible, avoid the use of ceritinib, a time-dependent inhibitor of CYP3A4, with CYP3A4 substrates such as buprenorphine since buprenorphine exposure may be increased. Additionally, ceritinib and buprenorphine are associated with QT prolongation. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If co-administration is unavoidable, consider a buprenorphine dose reduction and monitor for buprenorphine toxicity. Cetirizine: Additive drowsiness may occur if cetirizine/levocetirizine is administered with other drugs that depress the CNS, such as buprenorphine. Cetirizine; Pseudoephedrine: Additive drowsiness may occur if cetirizine/levocetirizine is administered with other drugs that depress the CNS, such as buprenorphine. Chlophedianol; Dexchlorpheniramine; Pseudoephedrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chloral Hydrate: If concurrent use of chloral hydrate and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Sedation, coma, or respiratory depression may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chloramphenicol: The plasma concentrations of CYP3A4 substrates such as buprenorphine and its metabolite, norbuprenorphine, may be elevated when administered concurrently with strong CYP3A4 inhibitors such as chloramphenicol. During co-administration, use the lowest buprenorphine starting dose and slowly titrate to desired effect. Monitoring for adverse effects, such as CNS side effects or respiratory depression, is advisable. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied. Chlorcyclizine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlordiazepoxide: Concomitant use of mixed opiate agonists/antagonists with benzodiazepines may cause respiratory depression, hypotension, profound sedation, and death. Limit the use of mixed opiate agonists/antagonists with benzodiazepines to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. If a mixed opiate agonist/antagonist is initiated in a patient taking a benzodiazepine, use a lower initial dose of the mixed opiate agonist/antagonist and titrate to clinical response. Reduce injectable buprenorphine dose by 1/2, and for the buprenorphine transdermal patch, start therapy with the 5 mcg/hour patch. If a benzodiazepine is prescribed for an indication other than epilepsy in a patient taking a mixed opiate agonist/antagonist, use a lower initial dose of the benzodiazepine and titrate to clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. Chlordiazepoxide; Clidinium: Concomitant use of mixed opiate agonists/antagonists with benzodiazepines may cause respiratory depression, hypotension, profound sedation, and death. Limit the use of mixed opiate agonists/antagonists with benzodiazepines to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. If a mixed opiate agonist/antagonist is initiated in a patient taking a benzodiazepine, use a lower initial dose of the mixed opiate agonist/antagonist and titrate to clinical response. Reduce injectable buprenorphine dose by 1/2, and for the buprenorphine transdermal patch, start therapy with the 5 mcg/hour patch. If a benzodiazepine is prescribed for an indication other than epilepsy in a patient taking a mixed opiate agonist/antagonist, use a lower initial dose of the benzodiazepine and titrate to clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. Chloroquine: Buprenorphine should be avoided in combination with chloroquine. Chloroquine administration is associated with an increased risk of QT prolongation and torsades de pointes (TdP). Buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If coadministration is necessary, carefully assess the risks versus benefits of concurrent use. Chlorpheniramine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Codeine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as codeine. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of codeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including codeine. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Dextromethorphan: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Dextromethorphan; Phenylephrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Dihydrocodeine; Phenylephrine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as dihydrocodeine. Dihydrocodeine is found in several combination cough products. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression if buprenorphine is used with dihydrocodeine. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of dihydrocodeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including dihydrocodeine. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Dihydrocodeine; Pseudoephedrine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as dihydrocodeine. Dihydrocodeine is found in several combination cough products. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression if buprenorphine is used with dihydrocodeine. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of dihydrocodeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including dihydrocodeine. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Guaifenesin; Hydrocodone; Pseudoephedrine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as hydrocodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. The opiate antagonists naloxone and naltrexone are pharmacologic opposites of hydrocodone. These drugs can block the actions of hydrocodone and, if administered to patients who have received chronic hydrocodone, can produce acute withdrawal and/or reduce the analgesic effect of hydrocodone. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Hydrocodone: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as hydrocodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. The opiate antagonists naloxone and naltrexone are pharmacologic opposites of hydrocodone. These drugs can block the actions of hydrocodone and, if administered to patients who have received chronic hydrocodone, can produce acute withdrawal and/or reduce the analgesic effect of hydrocodone. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Hydrocodone; Phenylephrine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as hydrocodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. The opiate antagonists naloxone and naltrexone are pharmacologic opposites of hydrocodone. These drugs can block the actions of hydrocodone and, if administered to patients who have received chronic hydrocodone, can produce acute withdrawal and/or reduce the analgesic effect of hydrocodone. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Hydrocodone; Pseudoephedrine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as hydrocodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. The opiate antagonists naloxone and naltrexone are pharmacologic opposites of hydrocodone. These drugs can block the actions of hydrocodone and, if administered to patients who have received chronic hydrocodone, can produce acute withdrawal and/or reduce the analgesic effect of hydrocodone. If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Phenylephrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpheniramine; Pseudoephedrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Chlorpromazine: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of chlorpromazine and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Chlorpromazine has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If concurrent use of chlorpromazine and buprenorphine is necessary, consider a dose reduction of one or both drugs. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Cimetidine: Since the metabolism of buprenorphine is mediated by the CYP3A4 isozyme, co-administration of drugs that inhibit CYP3A4, such as cimetidine, may cause decreased clearance of buprenorphine. Thus, there is a potential for excessive buprenorphine-related side effects. Ciprofloxacin: Buprenorphine should be used cautiously and with close monitoring with ciprofloxacin. Rare cases of QT prolongation and torsade de pointe (TdP) have been reported with ciprofloxacin during post-marketing surveillance. Buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Cisapride: QT prolongation and ventricular arrhythmias, including torsade de pointes (TdP) and death, have been reported with cisapride. Because buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP), coadministration is contraindicated. Citalopram: Due to the potential for QT prolongation, coadministration of citalopram and buprenorphine should be avoided. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Citalopram causes dose-dependent QT interval prolongation. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If concurrent therapy is considered essential, ECG monitoring is recommended. In addition, concurrent use of opioids with other drugs that modulate serotonergic function, such as SSRIs, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Clarithromycin: Due to the potential for QT prolongation, cautious use and close monitoring are advisable if concurrent use of clarithromycin and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Clarithromycin also has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, since the metabolism of buprenorphine is mediated by CYP3A4, co-administration of a strong CYP3A4 inhibitor such as clarithromycin may decrease the clearance of buprenorphine resulting in prolonged or increased opioid effects. If co-administration is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider dose adjustments until stable drug effects are achieved. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied, and the effect may be dependent on the route of administration. Class IA Antiarrhythmics: Buprenorphine should be avoided in combination with Class IA antiarrhythmics. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Clemastine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Clobazam: Concomitant use of mixed opiate agonists/antagonists with benzodiazepines may cause respiratory depression, hypotension, profound sedation, and death. Limit the use of mixed opiate agonists/antagonists with benzodiazepines to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. If a mixed opiate agonist/antagonist is initiated in a patient taking a benzodiazepine, use a lower initial dose of the mixed opiate agonist/antagonist and titrate to clinical response. Reduce injectable buprenorphine dose by 1/2, and for the buprenorphine transdermal patch, start therapy with the 5 mcg/hour patch. If a benzodiazepine is prescribed for an indication other than epilepsy in a patient taking a mixed opiate agonist/antagonist, use a lower initial dose of the benzodiazepine and titrate to clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. Clomipramine: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of tricyclic antidepressants (TCAs) and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Tricyclic antidepressants share pharmacologic properties similar to the Class IA antiarrhythmic agents and may prolong the QT interval, particularly in overdose or with higher-dose prescription therapy (elevated serum concentrations). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, concurrent use of opioids with other drugs that modulate serotonergic function, such as TCAs, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Lastly, concomitant use of buprenorphine with other CNS depressants, such as TCAs, can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. Consider a dose reduction of one or both drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Clonazepam: Concomitant use of mixed opiate agonists/antagonists with benzodiazepines may cause respiratory depression, hypotension, profound sedation, and death. Limit the use of mixed opiate agonists/antagonists with benzodiazepines to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. If a mixed opiate agonist/antagonist is initiated in a patient taking a benzodiazepine, use a lower initial dose of the mixed opiate agonist/antagonist and titrate to clinical response. Reduce injectable buprenorphine dose by 1/2, and for the buprenorphine transdermal patch, start therapy with the 5 mcg/hour patch. If a benzodiazepine is prescribed for an indication other than epilepsy in a patient taking a mixed opiate agonist/antagonist, use a lower initial dose of the benzodiazepine and titrate to clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. Clorazepate: Concomitant use of mixed opiate agonists/antagonists with benzodiazepines may cause respiratory depression, hypotension, profound sedation, and death. Limit the use of mixed opiate agonists/antagonists with benzodiazepines to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. If a mixed opiate agonist/antagonist is initiated in a patient taking a benzodiazepine, use a lower initial dose of the mixed opiate agonist/antagonist and titrate to clinical response. Reduce injectable buprenorphine dose by 1/2, and for the buprenorphine transdermal patch, start therapy with the 5 mcg/hour patch. If a benzodiazepine is prescribed for an indication other than epilepsy in a patient taking a mixed opiate agonist/antagonist, use a lower initial dose of the benzodiazepine and titrate to clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. Clozapine: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of clozapine and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Clozapine has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If concurrent use of clozapine and buprenorphine is necessary, consider a dose reduction of one or both drugs. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Cobicistat: The plasma concentrations of buprenorphine and its metabolite, norbuprenorphine, are elevated when administered concurrently cobicistat. Dose adjustents are not required; however clinical monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while buprenorphine is a CYP3A4 substrate. The plasma concentrations of buprenorphine and naloxone may be elevated when administered concurrently with cobicistat. When initiating buprenorphine; naloxone in patients currently on a regimen containing cobicistat and atazanavir or darunavir, use the lowest buprenorphine; naloxone starting dose and slowly titrate to desired effect. When initiating antiretroviral regimens containing cobicistat and atazanavir or darunavir to patients on buprenorphine; naloxone, an adjustment of buprenorphine; naloxone dose may be needed. Monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while buprenorphine is a CYP3A4 substrate. Cobicistat; Elvitegravir; Emtricitabine; Tenofovir Alafenamide: The plasma concentrations of buprenorphine and its metabolite, norbuprenorphine, are elevated when administered concurrently cobicistat. Dose adjustents are not required; however clinical monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while buprenorphine is a CYP3A4 substrate. The plasma concentrations of buprenorphine and its metabolite, norbuprenorphine, are elevated when administered concurrently with elvitegravir. Dose adjustments are not required; however clinical monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. The plasma concentrations of buprenorphine and naloxone may be elevated when administered concurrently with cobicistat. When initiating buprenorphine; naloxone in patients currently on a regimen containing cobicistat and atazanavir or darunavir, use the lowest buprenorphine; naloxone starting dose and slowly titrate to desired effect. When initiating antiretroviral regimens containing cobicistat and atazanavir or darunavir to patients on buprenorphine; naloxone, an adjustment of buprenorphine; naloxone dose may be needed. Monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while buprenorphine is a CYP3A4 substrate. Cobicistat; Elvitegravir; Emtricitabine; Tenofovir Disoproxil Fumarate: The plasma concentrations of buprenorphine and its metabolite, norbuprenorphine, are elevated when administered concurrently cobicistat. Dose adjustents are not required; however clinical monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while buprenorphine is a CYP3A4 substrate. The plasma concentrations of buprenorphine and its metabolite, norbuprenorphine, are elevated when administered concurrently with elvitegravir. Dose adjustments are not required; however clinical monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. The plasma concentrations of buprenorphine and naloxone may be elevated when administered concurrently with cobicistat. When initiating buprenorphine; naloxone in patients currently on a regimen containing cobicistat and atazanavir or darunavir, use the lowest buprenorphine; naloxone starting dose and slowly titrate to desired effect. When initiating antiretroviral regimens containing cobicistat and atazanavir or darunavir to patients on buprenorphine; naloxone, an adjustment of buprenorphine; naloxone dose may be needed. Monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while buprenorphine is a CYP3A4 substrate. Codeine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as codeine. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of codeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including codeine. Codeine; Guaifenesin: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as codeine. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of codeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including codeine. Codeine; Phenylephrine; Promethazine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as codeine. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of promethazine and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Promethazine has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If concurrent use of promethazine and buprenorphine is necessary, consider a dose reduction of one or both drugs. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Naloxone can antagonize the therapeutic efficacy of codeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including codeine. Codeine; Promethazine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as codeine. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of promethazine and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Promethazine has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If concurrent use of promethazine and buprenorphine is necessary, consider a dose reduction of one or both drugs. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Naloxone can antagonize the therapeutic efficacy of codeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including codeine. COMT inhibitors: Concomitant use of opiate agonists-antagonists with other central nervous system (CNS) depressants, such as COMT inhibitors, can potentiate the effects of the opiate agonists-antagonist and may lead to additive CNS or respiratory depression. Prior to concurrent use of a mixed opiate agonist-antagonist in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. If these agents are used together, reduced dosages may be necessary. Carefully monitor the patient for hypotension, CNS depression, and respiratory depression. Conivaptan: According to the manufacturer, concomitant use of conivaptan, a strong CYP3A4 inhibitor, and CYP3A substrates, such as buprenorphine, should be avoided. Coadministration of conivaptan with other CYP3A substrates has resulted in increased mean AUC values (2 to 3 times). Theoretically, similar pharmacokinetic effects could be seen with buprenorphine. Treatment with buprenorphine may be initiated no sooner than 1 week after completion of conivaptan therapy. Crizotinib: Buprenorphine should be used cautiously and with close monitoring with crizotinib. Crizotinib has been associated with QT prolongation; buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. According to the manufacturer of crizotinib, ECG monitoring is recommended if coadministration with another drug that prolongs the QT interval is necessary. In addition, since the metabolism of buprenorphine is mediated by CYP3A4, co-administration of a CYP3A4 inhibitor such as crizotinib may decrease the clearance of buprenorphine resulting in prolonged or increased opioid effects. If co-administration is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider dose adjustments until stable drug effects are achieved. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied. Cyclizine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Cyclobenzaprine: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of cyclobenzaprine and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Cyclobenzaprine has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If concurrent use of cyclobenzaprine and buprenorphine is necessary, consider a dose reduction of one or both drugs. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Cyproheptadine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Dalfopristin; Quinupristin: Dalfopristin; quinupristin is a major inhibitor of cytochrome P450 3A4 and may decrease the elimination of drugs metabolized by this enzyme including buprenorphine. Dantrolene: Concomitant use of buprenorphine with other CNS depressants can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur; examples of other CNS depressants can include skeletal muscle relaxants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Darunavir: Concomitant administration of darunavir with buprenorphine increases the concentrations of norbuprenorphine, a metabolite of buprenorphine. Buprenorphine undergoes both N-dealkylation to norbuprenorphine and glucuronidation. The N-dealkylation pathway is mediated by the cytochrome CYP3A4 isozyme, which in inhibited by darunavir. Clinical monitoring is recommended if these drugs are used together. Darunavir; Cobicistat: Concomitant administration of darunavir with buprenorphine increases the concentrations of norbuprenorphine, a metabolite of buprenorphine. Buprenorphine undergoes both N-dealkylation to norbuprenorphine and glucuronidation. The N-dealkylation pathway is mediated by the cytochrome CYP3A4 isozyme, which in inhibited by darunavir. Clinical monitoring is recommended if these drugs are used together. The plasma concentrations of buprenorphine and its metabolite, norbuprenorphine, are elevated when administered concurrently cobicistat. Dose adjustents are not required; however clinical monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while buprenorphine is a CYP3A4 substrate. The plasma concentrations of buprenorphine and naloxone may be elevated when administered concurrently with cobicistat. When initiating buprenorphine; naloxone in patients currently on a regimen containing cobicistat and atazanavir or darunavir, use the lowest buprenorphine; naloxone starting dose and slowly titrate to desired effect. When initiating antiretroviral regimens containing cobicistat and atazanavir or darunavir to patients on buprenorphine; naloxone, an adjustment of buprenorphine; naloxone dose may be needed. Monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while buprenorphine is a CYP3A4 substrate. Dasabuvir; Ombitasvir; Paritaprevir; Ritonavir: Concurrent use of buprenorphine and ritonavir is considered contraindicated. Buprenorphine, a CYP3A4 substrate, and ritonavir, a CYP3A4 inhibitor, are both associated with a risk for QT prolongation and torsade de pointes (TdP). The combined use of two drugs that can cause QT prolongation and TdP, along with a possible increased risk for these effects due to elevated plasma concentrations of buprenorphine via CYP3A4 inhibition by ritonavir, warrants a contraindication for concurrent use. Dasatinib: Buprenorphine should be used cautiously and with close monitoring with dasatinib. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). In vitro studies have shown that dasatinib has the potential to prolong cardiac ventricular repolarization (prolong QT interval). Cautious dasatinib administration is recommended to patients taking drugs that lead to QT prolongation. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, the plasma concentrations of buprenorphine, a CYP3A4 substrate, may be increased when administered concurrently with dasatinib, a time-dependent, weak inhibitor of CYP3A4, further increasing the risk of toxicity. If these drugs are used together, monitor for evidence of QT prolongation and other buprenorphine-related adverse reactions, such as respiratory depression and sedation. Daunorubicin: If concurrent use of an anthracycline chemotherapy agent and buprenorphine is necessary, cautious use and close monitoring are advisable. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Acute cardiotoxicity can occur during administration of daunorubicin; cumulative, dose-dependent cardiomyopathy may also occur. Acute ECG changes during anthracycline therapy are usually transient and include ST-T wave changes, QT prolongation, and changes in QRS voltage. Sinus tachycardia is the most common arrhythmia, but other arrhythmias such as supraventricular tachycardia (SVT), ventricular tachycardia, heart block, and premature ventricular contractions (PVCs) have been reported. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Degarelix: Buprenorphine should be used cautiously and with close monitoring with degarelix. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval, such as degarelix. If these drugs are used together, consider the potential for additive effects on the QT interval. Delavirdine: Delavirdine is a potent inhibitor of the CYP3A4 and increased plasma concentrations of drugs extensively metabolized by this enzyme, such as buprenorphine, should be expected with concurrent use of delavirdine. Desflurane: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of halogenated anesthetics and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Halogenated anesthetics have a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, during co-administration of buprenorphine with other CNS depressants, hypotension, profound sedation, coma, respiratory depression, or death may occur. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects. Monitor patients for sedation or respiratory depression. The buprenorphine dose may also need to be lowered when given with drugs that reduce hepatic blood flow, such as halothane, which causes a reduction in hepatic blood flow by about 30%. Desipramine: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of tricyclic antidepressants (TCAs) and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Tricyclic antidepressants share pharmacologic properties similar to the Class IA antiarrhythmic agents and may prolong the QT interval, particularly in overdose or with higher-dose prescription therapy (elevated serum concentrations). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, concurrent use of opioids with other drugs that modulate serotonergic function, such as TCAs, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Lastly, concomitant use of buprenorphine with other CNS depressants, such as TCAs, can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. Consider a dose reduction of one or both drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Desvenlafaxine: Concurrent use of opioids with other drugs that modulate serotonergic function, such as SNRIs (e.g., desvenlafaxine, duloxetine, milnacipran, levomilnacipran, venlafaxine), has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Dexchlorpheniramine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Dexchlorpheniramine; Dextromethorphan; Pseudoephedrine: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Dexmedetomidine: If concurrent use of dexmedetomidine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Monitor patients for sedation or respiratory depression. Dextromethorphan; Diphenhydramine; Phenylephrine: If concurrent use of diphenhydramine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Increased sedation, coma, and respiratory depression may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Dextromethorphan; Promethazine: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of promethazine and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Promethazine has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If concurrent use of promethazine and buprenorphine is necessary, consider a dose reduction of one or both drugs. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Diazepam: Concomitant use of mixed opiate agonists/antagonists with benzodiazepines may cause respiratory depression, hypotension, profound sedation, and death. Limit the use of mixed opiate agonists/antagonists with benzodiazepines to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. If a mixed opiate agonist/antagonist is initiated in a patient taking a benzodiazepine, use a lower initial dose of the opiate and titrate to clinical response. Reduce injectable buprenorphine dose by 1/2, and for the buprenorphine transdermal patch, start therapy with the 5 mcg/hour patch. If parental diazepam is used with an opiate agonist, reduce the mixed opiate agonist/antagonist dosage by at least 1/3. If a benzodiazepine is prescribed for an indication other than epilepsy in a patient taking a mixed opiate agonist/antagonist, use a lower initial dose of the benzodiazepine and titrate to clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. Dihydrocodeine; Guaifenesin; Pseudoephedrine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as dihydrocodeine. Dihydrocodeine is found in several combination cough products. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression if buprenorphine is used with dihydrocodeine. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. Naloxone can antagonize the therapeutic efficacy of dihydrocodeine in addition to precipitating withdrawal symptoms in patients who are physically dependent on opiate drugs including dihydrocodeine. Diltiazem: Diltiazem is an inhibitor of the CYP3A4 isoenzyme. Co-administration with diltiazem may lead to an increase in serum levels of drugs that are CYP3A4 substrates, such as buprenorphine. Dimenhydrinate: If concurrent use of sedating H1-blockers and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Diphenhydramine: If concurrent use of diphenhydramine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Increased sedation, coma, and respiratory depression may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Diphenhydramine; Hydrocodone; Phenylephrine: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as hydrocodone. In these cases, health care professionals must exercise caution in opiate agonist dose selection, as higher doses of an opiate agonist may be required to compete with buprenorphine at the mu-receptor. Management strategies may include adding a short-acting opiate agonist to achieve analgesia in the presence of buprenorphine, discontinuation of buprenorphine and use of an opiate agonist to avoid withdrawal and achieve analgesia, or conversion of buprenorphine to methadone while using additional opiate agonists if needed. Closely monitor patients for CNS or respiratory depression. When buprenorphine is used for analgesia, avoid co-use with opiate agonists. Buprenorphine may cause withdrawal symptoms in patients receiving chronic opiate agonists as well as possibly potentiate CNS, respiratory, and hypotensive effects. The additive or antagonistic effects are dependent upon the dose of the opiate agonist used; antagonistic effects are more common at low to moderate doses of the opiate agonist. The opiate antagonists naloxone and naltrexone are pharmacologic opposites of hydrocodone. These drugs can block the actions of hydrocodone and, if administered to patients who have received chronic hydrocodone, can produce acute withdrawal and/or reduce the analgesic effect of hydrocodone. If concurrent use of diphenhydramine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Increased sedation, coma, and respiratory depression may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Diphenhydramine; Ibuprofen: If concurrent use of diphenhydramine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Increased sedation, coma, and respiratory depression may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Diphenhydramine; Phenylephrine: If concurrent use of diphenhydramine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Increased sedation, coma, and respiratory depression may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Dofetilide: Dofetilide, a Class III antiarrhythmic agent, is associated with a well-established risk of QT prolongation and torsades de pointes (TdP). Because buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP), coadministration is contraindicated. Dolasetron: Buprenorphine should be used cautiously and with close monitoring with dolasetron. Dolasetron has been associated with a dose-dependant prolongation in the QT, PR, and QRS intervals on an electrocardiogram. Buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If these drugs are used together, consider the potential for additive effects on the QT interval. Donepezil: Buprenorphine should be used cautiously and with close monitoring with donepezil. Case reports indicate that QT prolongation and torsade de pointes (TdP) can occur during donepezil therapy. Buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If these drugs are used together, consider the potential for additive effects on the QT interval. Donepezil; Memantine: Buprenorphine should be used cautiously and with close monitoring with donepezil. Case reports indicate that QT prolongation and torsade de pointes (TdP) can occur during donepezil therapy. Buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If these drugs are used together, consider the potential for additive effects on the QT interval. Doxepin: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of tricyclic antidepressants (TCAs) and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Tricyclic antidepressants share pharmacologic properties similar to the Class IA antiarrhythmic agents and may prolong the QT interval, particularly in overdose or with higher-dose prescription therapy (elevated serum concentrations). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, concurrent use of opioids with other drugs that modulate serotonergic function, such as TCAs, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Lastly, concomitant use of buprenorphine with other CNS depressants, such as TCAs, can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. Consider a dose reduction of one or both drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Doxorubicin: If concurrent use of an anthracycline chemotherapy agent and buprenorphine is necessary, cautious use and close monitoring are advisable. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Acute cardiotoxicity can occur during administration of doxorubicin; cumulative, dose-dependent cardiomyopathy may also occur. Acute ECG changes during anthracycline therapy are usually transient and include ST-T wave changes, QT prolongation, and changes in QRS voltage. Sinus tachycardia is the most common arrhythmia, but other arrhythmias such as supraventricular tachycardia (SVT), ventricular tachycardia, heart block, and premature ventricular contractions (PVCs) have been reported. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Doxylamine: If concurrent use of doxylamine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Doxylamine; Pyridoxine: If concurrent use of doxylamine and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Dronabinol, THC: Concomitant use of buprenorphine with other CNS depressants can lead to additive CNS depressive effects. Hypotension, profound sedation, coma, respiratory depression, or death may occur; examples of other CNS depressants can include dronabinol. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Consider the patient's use of alcohol or illicit drugs. A dose reduction of one or both drugs may be warranted. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Dronedarone: Dronedarone administration is associated with a dose-related increase in the QTc interval. The increase in QTc is approximately 10 milliseconds at doses of 400 mg twice daily (the FDA-approved dose) and up to 25 milliseconds at doses of 1600 mg twice daily. Because buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP), coadministration is contraindicated. Droperidol: Mixed opiate agonists/antagonists have additive or potentiating effects with droperidol. Following administration of droperidol, lower doses of the other CNS depressant should be used. Duloxetine: Concurrent use of opioids, such as buprenorphine, with other drugs that modulate serotonergic function, such as SNRIs, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Efavirenz: If possible, avoid coadministration of efavirenz and buprenorphine, as use of these medications together may increase the risk for QT prolongation and torsade de pointes (TdP). QT prolongation has been observed with use of efavirenz. Although data are limited, the manufacturer of efavirenz recommends an alternative antiretroviral be considered for patients receiving medications with a known risk for TdP. Buprenorphine has been associated with QT prolongation and has a possible risk of TdP. In addition, efavirenz induces CYP3A4 and may decrease serum concentrations of drugs metabolized by this enzyme, such as buprenorphine. Efavirenz has been shown to decrease the AUC of buprenorphine by 50% and the norbuprenorphine AUC by 71%. No withdrawal symptoms have been reported and no dosage adjustments are recommended; however, monitor patients for withdrawal symptoms. Efavirenz; Emtricitabine; Tenofovir: If possible, avoid coadministration of efavirenz and buprenorphine, as use of these medications together may increase the risk for QT prolongation and torsade de pointes (TdP). QT prolongation has been observed with use of efavirenz. Although data are limited, the manufacturer of efavirenz recommends an alternative antiretroviral be considered for patients receiving medications with a known risk for TdP. Buprenorphine has been associated with QT prolongation and has a possible risk of TdP. In addition, efavirenz induces CYP3A4 and may decrease serum concentrations of drugs metabolized by this enzyme, such as buprenorphine. Efavirenz has been shown to decrease the AUC of buprenorphine by 50% and the norbuprenorphine AUC by 71%. No withdrawal symptoms have been reported and no dosage adjustments are recommended; however, monitor patients for withdrawal symptoms. Elbasvir; Grazoprevir: Administering buprenorphine with elbasvir; grazoprevir may result in elevated buprenorphine plasma concentrations. Buprenorphine is a substrate of CYP3A; grazoprevir is a weak CYP3A inhibitor. If these drugs are used together, closely monitor for signs of adverse events. Eletriptan: Concurrent use of opioids with other drugs that modulate serotonergic function, such as selective serotonin-receptor agonists ('triptans'), has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment with buprenorphine and a triptan is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Eliglustat: Buprenorphine should be used cautiously and with close monitoring with eliglustat. Eliglustat is predicted to cause PR, QRS, and/or QT prolongation at significantly elevated plasma concentrations. Buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If these drugs are used together, consider the potential for additive effects on the QT interval. Elvitegravir: The plasma concentrations of buprenorphine and its metabolite, norbuprenorphine, are elevated when administered concurrently with elvitegravir. Dose adjustments are not required; however clinical monitoring for adverse effects, such as CNS side effects or respiratory depression, is recommended during coadministration. Emtricitabine; Rilpivirine; Tenofovir alafenamide: Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval, such as rilpivirine, Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation. Coadministration may further increase the risk of QT prolongation and TdP. Emtricitabine; Rilpivirine; Tenofovir disoproxil fumarate: Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval, such as rilpivirine, Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation. Coadministration may further increase the risk of QT prolongation and TdP. Enflurane: Due to the potential for QT prolongation and additive CNS depressant effects, cautious use and close monitoring are advisable if concurrent use of halogenated anesthetics and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Halogenated anesthetics have a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, during co-administration of buprenorphine with other CNS depressants, hypotension, profound sedation, coma, respiratory depression, or death may occur. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects. Monitor patients for sedation or respiratory depression. The buprenorphine dose may also need to be lowered when given with drugs that reduce hepatic blood flow, such as halothane, which causes a reduction in hepatic blood flow by about 30%. Entacapone: Concomitant use of opiate agonists-antagonists with other central nervous system (CNS) depressants, such as COMT inhibitors, can potentiate the effects of the opiate agonists-antagonist and may lead to additive CNS or respiratory depression. Prior to concurrent use of a mixed opiate agonist-antagonist in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. If these agents are used together, reduced dosages may be necessary. Carefully monitor the patient for hypotension, CNS depression, and respiratory depression. Enzalutamide: Enzalutamide is a strong CYP3A4 inducer and may decrease the systemic exposure and therapeutic efficacy of buprenorphine, a CYP3A4 substrate. Monitor for potential reduction in efficacy or buprenorphine withdrawal symptoms. Epirubicin: If concurrent use of an anthracycline chemotherapy agent and buprenorphine is necessary, cautious use and close monitoring are advisable. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Acute cardiotoxicity can occur during administration of epirubicin; cumulative, dose-dependent cardiomyopathy may also occur. Acute ECG changes during anthracycline therapy are usually transient and include ST-T wave changes, QT prolongation, and changes in QRS voltage. Sinus tachycardia is the most common arrhythmia, but other arrhythmias such as supraventricular tachycardia (SVT), ventricular tachycardia, heart block, and premature ventricular contractions (PVCs) have been reported. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. Eribulin: Buprenorphine should be used cautiously and with close monitoring with eribulin. Eribulin has been associated with QT prolongation. Buprenorphine has also been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. If eribulin and buprenorphine must be coadministered, ECG monitoring is recommended; closely monitor the patient for QT interval prolongation. Erythromycin: Due to the potential for QT prolongation, cautious use and close monitoring are advisable if concurrent use of erythromycin and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Erythromycin also has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, since the metabolism of buprenorphine is mediated by CYP3A4, co-administration of a CYP3A4 inhibitor such as erythromycin may decrease the clearance of buprenorphine resulting in prolonged or increased opioid effects. If co-administration is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider dose adjustments until stable drug effects are achieved. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied, and the effect may be dependent on the route of administration. Erythromycin; Sulfisoxazole: Due to the potential for QT prolongation, cautious use and close monitoring are advisable if concurrent use of erythromycin and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Erythromycin also has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, since the metabolism of buprenorphine is mediated by CYP3A4, co-administration of a CYP3A4 inhibitor such as erythromycin may decrease the clearance of buprenorphine resulting in prolonged or increased opioid effects. If co-administration is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider dose adjustments until stable drug effects are achieved. The effect of CYP3A4 inhibitors on buprenorphine implants has not been studied, and the effect may be dependent on the route of administration. Escitalopram: Due to the potential for QT prolongation, cautious use and close monitoring are advisable if concurrent use of escitalopram and buprenorphine is necessary. Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). Escitalopram also has a possible risk for QT prolongation and TdP. FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval. In addition, concurrent use of opioids with other drugs that modulate serotonergic function, such as SSRIs, has resulted in serotonin syndrome in some cases. Serotonin syndrome is characterized by the rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. If combination treatment is required, patients should be carefully observed, particularly during treatment initiation and during dose adjustments of the serotonergic drug; discontinue buprenorphine if serotonin syndrome is suspected. Eslicarbazepine: Close monitoring of the patient is recommended if a CYP3A4 inducer, such as eslicarbazepine, is used with a CYP3A4 substrate, such as buprenorphine. Moderate to strong CYP3A4 inducers may increase the hepatic metabolism of buprenorphine, which may lead to opiate withdrawal or inadequate pain control. This interaction is most significant if the enzyme-inducing agent is added after buprenorphine therapy has begun. Buprenorphine doses may need to be increased if a CYP3A4 inducer is added. Conversely, buprenorphine doses may need to be decreased if the CYP3A4 inducer discontinued. The effect of CYP3A4 inducers on buprenorphine implants has not been studied. Estazolam: Concomitant use of mixed opiate agonists/antagonists with benzodiazepines may cause respiratory depression, hypotension, profound sedation, and death. Limit the use of mixed opiate agonists/antagonists with benzodiazepines to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. If a mixed opiate agonist/antagonist is initiated in a patient taking a benzodiazepine, use a lower initial dose of the mixed opiate agonist/antagonist and titrate to clinical response. Reduce injectable buprenorphine dose by 1/2, and for the buprenorphine transdermal patch, start therapy with the 5 mcg/hour patch. If a benzodiazepine is prescribed for an indication other than epilepsy in a patient taking a mixed opiate agonist/antagonist, use a lower initial dose of the benzodiazepine and titrate to clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. Eszopiclone: If concurrent use of eszopiclone and buprenorphine is necessary, consider a dose reduction of one or both drugs because of the potential for additive pharmacological effects. Sedation, coma, or respiratory depression may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects; for the buprenorphine transdermal patch, start with the 5 mcg/hour patch. Monitor patients for sedation or respiratory depression. Ethanol: Alcohol is associated with CNS depression. The combined use of alcohol and CNS depressants can lead to additive CNS depression, which could be dangerous in tasks requiring mental alertness and fatal in overdose. Alcohol taken with other CNS depressants can lead to additive respiratory depression, hypotension, profound sedation, or coma. Consider the patient's use of alcohol or illicit drugs when prescribing CNS depressant medications. In many cases, the patient should receive a lower dose of the CNS depressant initially if the patient is not likely to be compliant with avoiding alcohol. Etomidate: If general anesthetics are required during treatment with buprenorphine, consider the potential for additive pharmacological effects during dose selection. Hypotension, profound sedation, coma, respiratory depression, or death may occur during co-administration of buprenorphine and other CNS depressants. Prior to concurrent use of buprenorphine in patients taking a CNS depressant, assess the level of tolerance to CNS depression that has developed, the duration of use, and the patient's overall response to treatment. Evaluate the patient's use of alcohol or illicit drugs. It is recommended that the injectable buprenorphine dose be halved for patients who receive other drugs with CNS depressant effects. Monitor patients for sedation or respiratory depression. Etravirine: Etravirine may decrease the systemic exposure and therapeutic efficacy of buprenorphine; monitor for potential reduction in efficacy or buprenorphine withdrawal symptoms. Buprenorphine is a CYP3A substrate, and etravirine is a moderate CYP3A inducer. Ezogabine: Buprenorphine has been associated with QT prolongation and has a possible risk of torsade de pointes (TdP). FDA-approved labeling for some buprenorphine products recommend avoiding use with Class 1A and Class III antiarrhythmic medications while other labels recommend avoiding use with any drug that has the potential to prolong the QT interval, such as ezogabine, In addition, due to the CNS effects of ezogabine, an enhanced CNS depressant effect may occur during concurrent use of other centrally-acting medications such as buprenorphine. Patients should be monitored for excessive somnolence during concurrent therapy with this agent. Fentanyl: Buprenorphine is a mixed opiate agonist/antagonist with strong affinity for the mu-receptor that may partially block the effects of full mu-receptor opiate agonists and reduce analgesic effects. In some cases of acute pain, trauma, or during surgical management, opiate-dependent patients receiving buprenorphine maintenance therapy may require concurrent treatment with opiate agonists, such as fentanyl. In